Tractor



April 16, 1940.

A w BONHAM, JR. ET AL .197.248

TRACTOR Filed Juhe 2s, 5 Sheets-Shet 1 INVENTORS: ANV. BONHAMMJR.

O INVENTORS:

A, W. 50M HAM. JR.

8 4 m n MW 9 Q u y 2 a e h s 5 L .A H 7 3 9 l R JR 6 M 2 Amm Wm J 0 m B n w. F

(Franz mm m WN A ril 16, 1940.

ATTORNEY April 16, 1940. A. w. BONHAM, JR, ,ET AL 2,197,248

TRACTOR Filed June 26, 1957 5 Sheets-Sheet 3 Q V NR Y R" MM AA mamfiw mow V. W: B MI N m m ATTORNEY A. w. BONHAM, JR ET AL 2,197,248

TRACTOR Filed June 26, 1937 5 Sheeis-Sheet 5 ATTORNEY.

April 16, 1940.

Patented Apr. 16, 1940 TRACTOR Albert W. Bonham, Jr., and Alvin B. Bonham, Clinton, Utah, assignors to Bonham Mann-i facturlng' Company, Montello, Nev., a corporation of Nevada Applicationlune 26, 1937, Serial No. 150,470

26 Claims.

This invention relates to a tractor, and more particularly a general utility tractor, that is to say, one which may be used for substantially all purposes for which horses, mules or other draft animals have heretofore been used. For example, the machine may be used with equal facility for plowing, harrowing, cultivating, scraping and many other purposes on farms, and for widely diversified haulage of modern contractors machinery, and the building of roads and in other engineering and industrial works.

The principal objects of the invention are:

First. To provide a tractor which may be completely controlled from a point remote from the tractor, by means of a pair of lines or reins in the hands of a driver although control of the machine may also be accomplished by an operator riding on the machine and handling the control device directly.

Second. To provide a machine which is positive and reliable in its action, but whose control mechanism is extremely sensitive and responsive.

Third. To be capable of making turns practically within its own length so as to economize space in turning at the ends of the furrows in plowing, or at the ends of the rows in cultivating farm crops, as well as in innumerable maneuvers in connection with industrial operations.

Fourth. To be capable of going straight ahead at a uniform speed, turningto either the right or the left, standing still for short periods or for periods of indefinite length, and backing either straight or to the right or left.

Fifth. To provide a tractor capable of being hitched to ordinary horse-drawn implements with only minor changes in implement hitch, such, for example, as replacing the ordinary long tongue .with a short tongue.

Sixth. To be so compact and maneuverable as to facilitate operation in close quarters where ordinarily movement is dimcult or even impossible.

Seventh. To be relatively simple in construction and operation, durable in use, and reasonable in cost.

Eighth. To be so conveniently handled by means of the reins or lines that the implement to which the tractor is attached can be manipulated even more effectively than if draft animals were used instead of the tractor, only one person being required for the entire performance.

Ninth. To provide clutch means, preferably in twin units, through which the power flow from a suitable source is routed direct from.a forward driving member or a reverse driving member to a driven member, which is to say that at no tim does the energy from the forward driving memher have to flow through any element of the reverse driving member, or vice versa.

- Tenth. To secure the maximum strength, com- 6 pactness and maneuverability through the novel disposition of four traction wheels, two wheels, preferably in tandem, being disposed on each side of a body frame, all the wheels being rotatably journaled on rigid axles, and having their tire l0 circumferences spaced apart from each other only so far as is necessary to provide adequate working clearance between the two.

In the drawings, which illustrate one embodiment of the invention,

Fig. 1 represents a plan;

Fig. 2 is a side elevation, a portion being broken away to show hidden parts;

Fig. 3 is a transverse vertical section taken on the line 3--3 in Fig; l, drawn to an enlarged 20 scale;

Fig. 4 is a fragmentary horizontal section taken on the line 4-4 in Fig. 3;

Fig. 5 is a longitudinal, vertical section taken on the line 5-5 in Fig. 3; the location of the 25 section plane 5-5 is also indicated. in Fig. 1,

but is drawn to the same scale as Fig. 3; the

drawbar being omitted;

Fig. 6 is a vertical section taken on' the line 6-5 in Fig. 3; or on the line 6A--5A, looking in the 0 direction of the arrows, but reflected from a mir-- ror plane; the locations of these two sections are also indicated in Fig. 1;

Fig. 'l is a vertical section, taken on the line 1-1 in Fig. 3; or on the line IA-1A looking in 35 the direction of the arrows, but reflected from a mirror plane;.the locations of these two sections are also indicated in Fig- 1;

Fig. 8 is a fragmentary portion of Fig. 5, showing an alternate position of certain parts;

Fig. 9 is a view similar to Fig. 8, but showing still another alternate position of the certain parts; and

- Fig. 10 is a flow sheet or diagram, indicating the flow of power from a suitable source, such 45 as an automotive engine, through the .various mechanical elements to the traction wheels, the control system to secure maximum maneuverability' being also indicated.

The tractor ofour invention may have any 50 suitable number of traction wheels, usually four, rotatably disposed on rigidly mounted axles, so as form a rigid wheel base. Preferably, each traction wheel is driven separately. The two wheels on each side of the tractor are preferably ar- 5 ranged in tandem fashion, and the maneuverability of the tractor depends upon the motion given the traction wheels on one side relative to the motion of the traction wheels on the other side.

An important novel .feature is a composite clutch means through which motion from a prime mover, such as an automotive engine, is transmitted to the traction wheels. The composite clutch means is in duplicate units, a right and a left, the two units being preferably spaced apart from each other transversely of the tractor, so as to admit transmission gearing between them.

Each clutch-means unit is used to drive independently and selectively the pair of traction wheels on its side of the tractor.

Another important novel feature is the composite power shaft on which the clutch-means units are mounted. The composite power shaft comprises preferably three sections, a centrally disposed driving section and two laterally disposed tributary or driven sections, all in axial alignment with one another. Each composite clutch-means unit includes two driving members and one driven member. The two driving members of each clutch-means unit are mounted on the driving section of the power shaft, and the driven member of each clutch-means unit is mounted on its corresponding tributary driven section of the power shaft.

The two clutch-means units are controlled independently of each other through a two-part rock shaft. Each of the two rock shaft parts is manipulated by its own suitable means, in this instance, a lever rigidly mounted on the respective part. Each rock shaft part has three significant positions, a forward, a neutral, and

a reverse or backing position. Novel features of the rock shaft control means willbecome apparent hereinafter. Suffice it to state at this point, that the control means is disposed in two or twin units loosely connected together so as to cause selectively the traction wheels on both sides of the tractor to be rotatable backward or forward, or so that the wheels on one side rotate in one direction while the wheels on the other side rotate simultaneously in the other direction, or vice versa. This, together with the compactness .of disposition of traction wheels and ruggedness of the framework, gives the assurance of advantageous maneuverability.

Rigidity and sturdiness of frame structure is attained by means of a centrally disposed box or housing in which the twin clutch-means units are disposed, as well as by the disposition of the front frame portion and rear frame portion, which are rigidly connected to the centrally disposed housing. Preferably, the automotive engine is mounted on the front frame portion, and a change-gear transmission on the rear frame portion.

An advantageous feature of each clutch-means unit is that the flow of power from each driving member to the driven member is direct, that is to say, does at no time make use of any of the elements of the other driving member to transmit its power to the driven member.

Referring to the drawings, the numeral indicates the chassis or framework, to which are rigidly secured the front axle El and rear axle 24. Both these axles hold a constant position at all times Rotatably mounted on the axles are the front wheels and the rear wheels 26,'

respectively. Naturally, the rigidity of the axles brings about the rigidity of the wheelbase.

At the front of the chassis 20 is mounted an engine (not shown) which is enclosed within a. hood 21. The'englne may be of any usual or suitable automotive design and be provided with a crankshaft 28 on which is mounted a flywheel 29 having preferably a housing 30. At the rear of the flywheel is a housing 3| which may be divided into a centrally disposed gear compartment 32 and two clutch compartments 34 and 35, opposite each other, and laterally adjacent the gear compartment on opposite sides thereof. At

the rear of the clutch housing is a transmission housing 36.

In each of the clutch compartments 34 and 35 is a clutch 31. The clutch, in its general construction, may, and in this instance does, follow certain characteristics of disk clutches as heretofore known. However, a difference is that the releasing mechanism is located on the driven side instead of being on the driving side as is customary in previous types. In particular, the present clutch comprises the heads 38 and 39 connected rigidly together by bolts 40. The heads 38 are fast on the respective stub shafts 4| which, at their outer extremities, carry the rigidly mounted twin sprockets 42. The inner clutch heads 39 are rotatably mounted on a shaft 43 carrying the .plates 50 is quite small and takes place on the bolts 40. To accomplish this movement, a plurality of rods 5| are spaced angularly around the outermost plate 50, and the inner end of each rod is rigidly secured therein. The rods 5| are slidable through openings in the head 38. Compression springs 52 react between the head 38 and the outer plate 50, and exert their pressure normally to hold the plates in frictional contact with the plates 49, whereby the clutch is operative to transmit motion from the shaft 43 to the head 38, and in turn to the stub shaft 4| and the twin sprocket 42. y

In order to disengage the clutch plates 50 from the plates 49, the rods 5| at their outer ends are rigidly secured in a disk 53 having the hub 54. Rotatably mounted on the hub 54 is an antifriction thrust bearing 56, which is secured in the hub 51 of a shifting yoke 58, the latter having a ball 59 at its lower end, which is held in a stationary socket 60. The upper end of the shifting yoke 58 carries the rotatably mounted roller 6| which is in contact with an oscillating cam 62. The cam 62 is given an angular swinging motion because of its rigid mounting on a rock shaft 63. The rock shaft has rigidly secured on it an operating lever 64, which is angularly movable in a slot in the cover 65 of the clutch housing.

Rigidly secured on the head 39 is an internal gear 61 which is in mesh with the planetary gears 68, and these, in turn, mesh with the sun gear 69' which is rigidly mounted on the shaft 43. The planetary gears are rotatably mounted on pins 10, which are rigidly secured in the web 1| of a drum 11, having the circumferential brake rim 12. The brake rim, Fig. 6, is encircled by a flexible band 13 having preferably a friction or brake lining 14.; Secured at or near theextremities of the gripping band I8, are the respective eyelets 15 and I6, and loosely secured in these eyelets are the respective bolts I8 and I9,

whose forked ends 80 are pivotally connected to a toggle member 8| having the leverarm 82. Engaging the lever arm 82 is a cam 83, which is rigidly mounted on the rocker shaft 63. Ohviously, when the operating lever 64 is pulled back, in the direction of the arrow 85, the lever arm 82 will be acted upon by the cam 83to tighten .-the band I3, and thereby to grip the drum 'II.

Each of the two clutch units in the respective compartments 34 and 35 has its own rocker shaft 63 independent of, but in axial alignment with, the other. The inner ends of the two rocker shafts 63 are in close proximity to each other, as shown in Fig. 3, and the extremity of each of the rocker shafts has rigidly mounted thereon a cam-86.

Extending around both cams 86, and straddling the two rocker shafts 63, is a yoke 81. This yoke carries a pin 89 on which are journaled two rollers 90, each roller being in alignment with a respective cam 86. The normal position of the yoke relative to the cams 86 is indicated in Fig. 5, but the yoke is movable back and forth, as and for a purpose presently to be described. The yoke is slotted at 9I in order to accommodate the shafts 68. The yoke has a forward stroke and a backward stroke, and disposed to control the backward stroke, is a stem 92, which extends into a check-pot 93. The stem 92 carries a piston 94, which is acted upon by a compression spring 95 operative to keep it in the normal position indicated in Fig. 4. The checkpot may advantageously be rigidly mounted on a wall of the casing 3|.

Motion from the engine crankshaft 28 is imparted to the shaft 43 in suitably'varying ratios through the transmission in the compartment 36. The transmission may consist of a splined shaft 96 which may be connected to the crankshaft by means of a sleeve coupling 91. The shaft 96 carries axially movable gears 98 and 99, which are adapted to mesh respectively with the gears IM and I02, the latter two gears being rigidly mounted on a shaft I04. Shaft I04 has rigidly mounted thereon a beveled pinion I05, which meshes with the bevel gear 45. As shown in Fig.

5, the transmission gears are in the neutral position where no motion is transmitted from the shaft 96 to the shaft I04.

For the purpose of preventing clashing between the gears of the transmission when shifting, a slidable disk I06 engages the splines on shaft 96 and has a limited movement axially thereon. This disk has a conical face and may be moved in the direction of the arrow by means of the stem I'I, which latter is slidably disposed in a wall of the housing, and has a button head I08 adapted to be pressed by the operator against the tension of the compression spring I09, this spring being-normally effective to keep the stem in the normal position indicated in Fig. 5.

In operative conjunction with the disk I06, is a mating disk H0, which latter is fast on the shaft I04, and has a conical face adapted to run with the conical face of the disk I06. When it is desired to shift gears, assuming the engine to be running, and the transmission to be neutral, the operator first pushes the button in the direction of the arrow, thereby bringing the disk I86 into engagement'with the disk 0 and causing the shaft I04 to rotate before shifting of the gears is attempted. The shaft I04 rotates preferably at a mean of the different transmission ratios, thereby facilitating the engagement of the desired gears substantially without clashing.

Shifting of the change gears 98 and 99, which are integral with each other, is accomplished by means of a lever II I operative to move a bar 2, slidably disposed in bearings H3, back or forth. Fixed on the bar H2 is a depending finger II4 whose lower extremity extends into a circumferential groove formed in the hub common to the two gears. At the discretion of the operator, the gear 98 may be brought selectively into mesh with the gear IOI, or the gear 99 be selectively brought into mesh with the gear I02. While only two change ears are shown in the present instance, more can be provided, three or four being frequently used.

A feature which adds greatly to the utility and maneuverability of the tractor relates to the drawbar I16, Figs. 1 and 2. The drawbar may junction with another bar I I8, the rear extremities of these bars forming between them a jaw for receiving a swiveled clevis II9 which is pivoted at I20. The drawbar is disposed to swing around a pivot I2I, and a frame member I24 conforms to an arc described from the pivot I2I as a center. The clevis is provided with guide rollers I25 spaced apart from each other and adapted to track on the member I24 as a guide for holding the clevis in alignment with the drawbar proper, excepting at such times as the tractor is making short-radius turns.

The clevis is forked at I26 and has the holes I21 located at varying levels, so as to receive connections from a tongue or otherpulling member of an implement, in the usual manner.

The advantage of this drawbar with its articulated clevis, is that so long as the rollers I25 remain on the track I24, the tractor pulls in a straight line from the pivot I2I, on through the Operation The operation of the tractor may be conveniently followed by reference to Fig. 10. This figure constitutes a flow sheet or diagram which clearly visualizes the flow of power from the prime mover or motive means to the traction wheels, and the manner of controlling the power.

The diagram shows broadly the relations of the operative parts of the tractor, one to another. Explanation of principal terms appearing in Fig. 10:

43Power-shaft driving section refers to shaft Power-shaft driven section L. and R. refers to the left and right stub shafts 4|.

Clutch-means forward driving member may include the hub 48, driving plates 49, and springs 52; right or left.

"Clutch-means reverse driving member may include the sun gear 69, planetary gears 88, and band I3; right or left.

Clutch-means driven member" may include the heads 38 and 39, driven plates 58, and internal gears 61; right or left.

"Clutch release mechanism" may include the shifting disk 53, shifting yoke 58, and oscillating cam 62; right or left.

Clutch reverse throw-in may include cam 83, toggle 8|, and lever arm 82; right or left.

Neutral rest means" may include the cam or earns 86, the yoke 81, and the check-pot 93.

Before starting the engine, the manual control or operating levers 84 should both stand in the neutral rest position. This allows the engine shaft to rotate without driving the tractor. The neutral rest position is attained by holding both control levers simultaneously in the neutral position for a certain minimum period of time, determined in a way to be presently explained. The neutral rest position is made use of in starting, or when it is desired to let the tractor stand stationary for any prolonged period. The control levers are released from the neutral rest position by pulling back slightly on one or the other or both levers, and then allowing both to move into the forward position. Supposing the shaft 43 to be rotating, then, with both levers in the forward position, the tractor moves straight ahead. If both levers are pulled simultaneously into the reverse position, the tractor moves straight back. If the left-hand lever is in forward, and the right-hand lever is in neutral, the tractor turns forward to the right. If now, the right-hand lever is pulled back into reverse, the tractor turns to the right double-quick. If the right-hand lever is in forward, and the left-hand lever is in neutral, the tractor turns forward to the left. If now, the left-hand lever is pulled clear back into reverse, the tractor turns to the left doublequick. In either of these double-quick maneuvers, the tractor may easily make a complete turn within the limits of its own wheelbase. In either case, the double-quick turn results because of tightening the proper brake band 13, whereby the corresponding drum I1 is held stationary, thus causing the motion from the sun gear 89 to reverse the driven member 38 with its stub shaft M.

In order to back to the right, the right-hand lever is placed in neutral and the left-hand lever in reverse. Now, letting\.the right-hand lever move forward, causes this backing turn to be made double-quick. In backing to the left, the procedure just described, is reversed.

The detailed functioning of the brake band I3 is indicated in Fig. 6. As shown, the lining I4 is supposed to'be relaxed on the drum rim I2, under the influence of a compression spring I38 strung on the bolt I8, and a tension spring I39, both springs tending to open out the band. Pulling the lever 64 back, into the reversing position 64a, tightens the band and brings the lining into gripping contact with the drum rim. Allowing the lever to be urged into the forward position 641), under the tension of springs 52, merely causes the hub of the cam 83 to idle in the concentric arcuate portion of the lever arm 82, and leaves the band and its lining relaxed.

A prominent advantage of the novel arrangement of the clutch means is that the fiow of power from the power-shaft driving section to the power-shaft driven section is always direct through either one or the other of the driving members, and never indirect through both simultaneously. This may be clearly seen in the flow sheet, Fig. 10. For example, in Fig. 3 it can be seen at a glance, that the flow of power from the shaft 43 through the clutch-means forward driving member, either L or R, as the case may be, diagrammed in Fig. 10, and composed of a driving hub 48 and plates 49, goes directly and only through these, to the respective clutch-means driven member, diagrammed in Fig. 10, which clutch-means driven member includes heads 38 and 39, driven plates 58, and internal gear 61. Similarly, in Fig. 3 it can be seen that the flow of power from the shaft 43 through the clutchmeans reverse driving member, either L or R, as the case may be, diagrammed in Fig. 10, and composed of a sun gear 89, planetary gears 88, and an internal gear 61 goes directly and only through these, to the same respective clutchmeans driven member aforementioned. Note particularly, that at such times as the driving 39 plates 49 are locked in engagement with the driven plates 50, the gripping band I3 is loose on the rim of drum 11, so that no power at all can flow through planetary'gears 68. Again, note that at such times as the drum TI is locked in the grip of the band I3, no power at all can flow through the driven plates 58, since these are detached from the driving plates 48.

For the sake of generalization, either the clutch-means forward driving member or the clutch-means reverse driving member" may be designated as: a driving member rotatable in a given direction, in which case the other one of the two clutch-means driving members can be referred to as: a second driving member rotatable in a direction opposite to the given direcion.

In comparing the invention with some prior clutches and planetary gear devices, it is to be kept in mind that the hub 48 of the clutch-means forwardu'iriving member, and the sun gear 69 of the clutch-means reverse driving member, are wholly independent of each other in operative action, and that their positions along the axis of the shaft 43, which naturally coincides with their own rotative axes, are fixed.

As heretofore constructed, certain clutch mechanisms transmit power from two drivers, one forward and one reverse, to a driven member, but in these mechanisms the flow of power through the forward driver is not direct, but includes in its line of flow the elements of the reverse driver. This may be amplified by stating that in the heretofore known clutch mechanisms, the reverse driver generally includes a planetary transmission mechanism, which is completely locked in the event that the forward driver is in use. The locked planetary transmission elements are positioned between the forward driver and the driven member, whereby there is a leverage exerted by the planetary gears, which the mechanical disadvantage, imposes twice the stress upon certain of the transmission members, including the driving and driven plates of the friction-disk clutch. Therefore, in transmitting an equal power, the clutch disks as used heretofore must be at least twice as massive as in the present novel construction, and naturally increase the wear and tear on the friction disks propor tionally.

The neutral-rest means functions as follows. In the neutral-rest position, both cams 86 occupy the position shown in Fig. 5, and are held yieldingly in that position under the urge of the springs 52. The spring urge forces the point I 35 sharply against the bottom of the respective roller 90 which occupies a recess I in the respective cam 86, as indicated in Fig. 5. In breaking the neutral-rest position of the cam, a slight pull back on either one or both of the levers causes the corresponding one, or both, of the cam portions I31 to push the yoke 81 to the left, far enough for the point I35 of either one or both cams to slip past the corresponding roller or rollers as the case may be, thereby in either case breaking the locking effect upon both rollers. The piston 94 moves to the left with the yoke and compresses the spring 95, at the same time causing the piston to draw air on its receding side past a cup leather I40, which acts as a check valve. At the proper moment the manual hold on the levers is suddenly relaxed, whereby both levers and their respective cams, under the urge of springs 52, are moved to their forward position, which is indicated in Fig. 9.

After relaxing the manual hold on the levers, the rollers are prevented from closely following the forward travel of the cam, because of the retarding action resulting from compression of air in the space I29, thus preventing the rollers from dropping quickly back into the recesses I30. The egress of the air from the space I29 is controlled by an adjustable needle valve IlI of ordinary construction, and this can be regulated to retard movement of the yoke 81 and rollers 9|]- the desired length of time. The rollers finally come to rest against the cam, as shown in Fig. 9.

The neutral-rest or locked position of the cams and rollers is attained by moving both levers 64 simultaneously into the neutral position, and holding them both simultaneously in the neutral position for a short though appreciable period of time, within which time period the rollers drop into the recesses I30 and lock with the cams, until again released. The air in the space I42 to the left of the piston, Fig.5, is in free communication with the atmosphere, and so offers no resistance either way to the movement of the piston.

Having fully described our invention, what we claim is:

1. A tractor having traction members. including in combination, two clutch-means units in axial alignment with, and. spaced apart from, each other, each of the clutch-means units comprising a forward driving member, a reverse driving member, and a driven member adapted to be selectively connected to either of the two driving members; gear means disposed to impart motion simultaneously to both the said clutch-means units; selective means operable to at least connect the forward driving member of one clutch-means unit with the driven member of that unit and simultaneously to connect the reverse driving member of the other clutchmeans unit with the driven member of this other unit, or vice versa; a transmission mechanism disposed to be selectively connected to the said gear means, and located to one side thereof, mo-

- tive means connected to the said transmission which the driving members of said clutch-means units and a member of the gear means are rigidly mounted, and stub shafts at both ends of the first-mentioned shaft, the driven members of said clutch-means units being rigidly mounted on the said stub shafts; and wherein the said means for transmitting motion extend from the stub shafts to the said traction members.

3. A tractor having traction members, in accordance with claim 1, wherein the said clutchmeans units are selectively operative either independently or together, as the case mayrequire, by means of two individual control mechanisms, each individual control mechanism including a rock shaft having a forward, neutral and a backing position, a cam effective to cause the forward driving member of the respective clutch-means units to engage the driven member of the clutch-means units in the forward position of the rock shaft, and a second cam effective to cause the reverse driving member of the clutch-means units to energize the driven member in the backing position of the rock shaft.

4. A tractor, including in combination, motive means, traction wheels operatively connected with the motive means; clutch means comprising two clutch units each having a forward driver, a reverse driver and a driven member adapted to be connected to either the forward driver or to the reverse driver independently of the other, the two clutch units being operative selectively to vary, or to cut off, the transmission of motion from the motive means to their corresponding traction wheels, and a control cam mechanism operative upon the said clutch means, the said control cam mechanism being actuated by independent manual motion thereto in only one direction to selectively cause the tractor to be driven forward, to stand still indefinitely, or to be driven backward.

5. A tractor, -inclucling in combination, a prime mover, traction wheels operatively connected therewith, clutch mechanism having a forward driving member and a reverse driving member operative individually and independently to transmit rotative motion from the prime mover to the traction wheels, a rock shaft having a forward position, a neutral position, and a reverse position; a mechanism selective to cause the engagement of the forward driving member of the clutch in the forward swing of the rock shaft, and a throw-in mechanism selective to engage the reverse driving member of the clutch in the reverse swing of the rock shaft.

6. A tractor, in accordance with claim 5, in which the rock shaft mechanism includes an oscillating cam having a neutral-rest position, a yoke having means effective to lock the cam in the neutral-rest position, cam means efiective to displace the yoke from the cam-locking position, and check means effective to properly retard the movement of the yoke from the displaced position back through the locking position.

'7. Clutch means, including in combination, a drive shaft, a stub shaft at each end of the drive shaft and in axial alignment therewith, a clutch driver member rigidly mounted on the drive shaft contiguous to each of the said stub shafts, a driven clutch member rigidly mounted on each of the stub shafts, gripping means selectively operated to connect or disconnect the clutch drivers to the respective driven clutch members, an internal gear rigidly connected to each driven clutch member, planetary gears in mesh with each internal gear, sun gears in mesh with the planetary gears and rigidly mounted on the said drive shaft, drums on which the planetary gears are rotatably mounted, brake bands encircling the drums, and means operable selectively and independently to cause the respective gripping means to connect either clutch driver with its driven clutch member or to cause either of said bands to grip or release its drum, the related gripping means and brake bands being operative alternatively whereby to provide two flow channels for motive power, wholly reversed and independent, from said drive shaft to each of said stub shafts.

8. Driving-control means, including in combination, two mutually interconnected control units, each having lever means movable back and forth from a forward-driving to a reversing position and vice versa, cam means effective to normally hold the lever means in the forwarddriving position or to urge the lever means toward the forward-driving position from any other position thereof, the said two lever means being selectively movable, either independently or together to a neutral-rest position substantially intermediate the forward-driving and reversing positions thereof, a releasable locking yoke disposed to hold the two lever means simultaneously in neutral-rest position for optional time periods, and dash-pot timing means connected to the locking yoke.

9. In a self-propelled vehicle having a driving shaft and a driven shaft, clutch mechanism for transmitting motion from the driving shaft to the driven shaft, said clutch mechanism comprising clutch means rigidly mounted on said driving shaft and clutch means rigidly mounted on said driven shaft, the two said clutch means being adapted for clutching engagement in transmitting rotative motion directly and unidirectionally from' said driving shaft to said driven shaft, and said clutch mechanism further comprising gear means rigidly mounted on said driving shaft, gear means rigidly mounted on said driven shaft, intermediate gear means in mesh with both said gear means and mounted for rotation per se and for free revolution about said driving shaft, and means for holding said last named gear means against free revolution about said driving shaft.

10. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime mover; control means for said clutch mechanism comprising a movable member having a forward drive position, a neutral-rest position and a reverse drive position, means for releasably locking said member in the neutral-rest position, means to release said locking means upon motion of said member from the neutral-rest position in one direction, and means for restraining said looking means from locking position to permit free return movement of said movable member through the neutral-rest position to the drive position in the opposite direction.

11. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime moveri control means for said clutch mechanism comprising two independently operable movable members each having a forward drive, a reverse drive and a neutral-rest position, means common to both movable members for releasably looking them in the neutral-rest position, and means to render said locking means inoperative when either of said members is in other than the neutral-rest position.

12. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime mover; control means for said clutch mechanism comprising two independently operable movable members each having a forward drive, a reverse drive and a neutral-rest position, means normally urging said movable members toward the forward drive position, means for moving said members in the opposite direction, means common to both movable members for releasably locking them in the neutral-rest position, and means to render said locking means inoperative when either of said members is in other than the neutral-rest position.

13. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime mover; control means for said clutch mechanism comprising two independently operable movable members each having a forward drive, a reverse drive and a neutral-rest position, and means common to both movable members operative to lock them in the neutral-rest position only when both of said movable members are in said neutral-rest position.

14. In a tractor including a prime mover, traction wheels, and clutch mechanism interposed between said prime mover and said traction wheels including selectively operable forward and reverse driving members for driving said traction wheels from said prime mover; control means for said clutch mechanism comprising a pair of independently movable rock shaft members each having a forward drive, a reverse drive and a neutral-rest position, each of said rock shaft members having a cam part, and means common to each of said rock shaft members for releasably locking said rock shaft members in the neutral-rest position, and said cam parts including surfaces operative to render said locking means inoperative when either of said rock shaft members is in other than the neutral-rest position.'

15. In a tractor including a prime mover, traction wheels, and clutch mechanism interposed between said prime mover and said traction wheels including selectively operable forward and reverse drivingmembers for driving said traction wheels from said prime mover; control means for said clutch mechanism comprising a pair of independently movable rock shaft members each having a forward drive, a reverse drive and a neutral-rest position, means normally urging said rock shaft members toward the forward drive position, means for moving said rock shaft members in the opposite direction, means common to each of said rock shaft members for releasably locking said rock shaft members in the neutral-rest position, and means operative to render said locking means inoperative when either of said rock shaft members is in other than the neutral-rest position.

16. In a tractor including a prime mover, traction wheels, and clutch mechanism interposed between said prime mover and said traction wheels including selectively operable forward and reverse driving members for driving said traction wheels from said prime mover; control means for said clutch mechanism comprising apair of independently movable rock shaft members each having a forward drive, a reverse drive and a neutral-rest position, each of said rock shaft members having a cam part, and means common to'each of said rock shaft members including a latch part yieldin'gly engaging said cam parts and operative to releasably lock said rock shaft members in the neutral-rest position, and said cam parts including portions to retain said-latch part in inoperative position when either of said rock shaft members is in other than neutral-rest position.

17. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime mover; control means for said clutch mechanism comprising a movable member having 'a forward drive position, a reverse drive position and a neutral-rest position intermediate said drive positions; means for releasably locking said movable member in said neutral-rest position; means to release said looking means upon motion of said movable member from neutral-rest position in one direction, means for restraining said locking means from locking position, and means for moving said movable member in the other direction through the neutral-rest position to the drive position in the.

other direction while said locking means is restrained from looking position. I

18. In a tractor including a prime mover, traction means, and clutch mechanism interposed between said prime mover and said traction means including selectively operable forward and reverse driving members for driving said traction means from said prime mover; control means for said clutch mechanism comprising a rock shaft having a forward drive position, a reverse drive position and a neutral-rest position intermediate said drive positions; a cam member fixed on said rock shaft, a movable yoke having means engaging said cam to lock the cam and associated rock shaft in neutral-rest position, yielding means normally urging said yoke to cam locking position, means for displacing said yoke from cam locking position upon motion of said cam and rock shaft from the neutral-rest position in one direction, and means to retard the return of said yoke to cam locking position to permit free return motion of said rock shaft through the neutral-rest position to the drive position in the opposite direction.

19.Driving control means for a tractor of the character described, including in combination two control units, each having lever means movable back and forth between. a forward-drive and a reverse-drive position; means effective normally to hold the lever means in one drive position and to urge the lever means toward said drive position from any other position thereof, the lever means being movable selectively either independently or together to a neutral-rest position intermediate the forward and reverse drive positions, and means common to both lever means.

operative to lock them in the neutral-rest position only when both of said lever means are in said neutral-rest position.

20. Driving control means for a tractor of the character described, including in combination two control units, each having lever means movable from said drive shaft to said driven means, re

neutral-rest position for optional time periods, 10

and means to release said holding means upon motion of one of said lever means from the neutral-rest position in the direction opposite to that in which the lever means are normally urged.

21. In a tractor including a frame, traction means at opposite sides thereof and a motor carried by said frame to drive said traction means; means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means. including a pair of clutch units, a drive shaft common to said ,units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member'rigidly mounted on said drive shaft, a driven clutch member carried by the related driven means to provide a direct drive connection verse .drive means including planetary gearing between said drive shaft and said driven means, said direct drive connection through the forward driving and driven clutch members being wholly. independent of elements of the reverse drive means; and means for controlling each clutch unit independently and selectively, to cause engagement of either the forward or reverse driv ing members of each clutch unit with the driven member thereof independently of the other clutch unit. T

22. In a tractor including a frame, traction means at opposite sides thereof and a motor carried by said frame to drive said traction means; means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means including a pair of clutch units, a drive shaft common to said units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member rigidly mounted on said drive shaft, a driven clutch member carried by the related driven means to provide a direct drive connectionfrom said drive shaftto said driven means, reverse drive means including planetary gearing between said drive shaft and said driven 'means, said direct driveconnection through the forward driving and driv'enclutch members being wholly independent of elements of the reverse drive means; and means for controlling each clutch unit independently and selectively to cause engagement ofeither the forward or reverse driving members of each clutch unit with the driven member thereof independently of the other clutch unit, said control means including a movable member associated with each clutch unit and movable back and forth between aforwarddrive and a reverse-drive position, means eifective normally to hold the movable. members in one drive position and to urge the same toward said position from any other position thereof.v

the movable members being movable selectively either independently or together to a neutral-rest position intermediate the forward and reverse drive position, means common to both movable members for releasably holding the same in the neutral-rest position, and'means for rendering said holding means inoperative when either of said members is in other than the neutral-rest position.

23. In a tractor including a frame, traction means at opposite sides thereof and a motor carried by said frame to drive said traction means; means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means including a pair of 'clutch units, a drive shaft common to said units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member rigidly mounted on said drive shaft, a driven clutch member carried by the related driven means to provide a direct drive connection from said drive shaft to said driven means, reverse drive means including planetary gearing between said drive shaft and said driven means, said direct drive connection through the forward driving and driven clutch members being wholly independent of elements of the reverse drive means; and means for controlling each clutch unit independently and selectively to cause engagement of either the forward or reverse driving members of each clutch unit with the driven member thereof independently of the other clutch unit, said control means including a rock shaft associated with each unit, each rock shaft having a forward drive position, a neutral-rest position and a reverse drive position, locking means common to both rock shafts for releasably holding the same in the neutral-rest position, and means to release said locking means upon motion of either rock shaft from the neutral-rest position.

24. In a tractor including a frame, traction means at opposite sides thereof and a motor carried by said frame to drive said traction means;

means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means including a pair of clutch units, a drive shaft common to said units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member rigidly mounted on said drive shaft, a driven clutch member carried by the related driven means to provide a direct drive connection from said drive shaft to said driven means, reverse drive means including planetary gearing between said drive shaft and said driven means, said direct drive connection through the forward driving and driven clutch members being wholly independent of elements of the reverse drive means; and means for controlling each clutch unit independently and, selectively to cause engagement of either the forward or reverse driving members of each clutch unit with the driven member thereof independently of the other clutch unit, said control means including lever means associated with each clutch unit and movable back and forth between a forward-drive and a reverse-drive position, means effective normally ,to hold the lever means in one drive position and to urge the lever means toward said position from any other position thereof, the lever means being movable selectively either independently or together to a neutral-rest position-intermediate the forward and reverse drive positions, and meansv common to both lever means for releasably holding them in the neutral-rest position, said means being operative to lock said levers only when both are in said neutral-rest position.

25. In a tractor including a frame, traction means at opposite sides thereof, and a motor carried by said frame to drive said traction means; means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means including a pair of clutch units, a drive shaft common to said units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member mounted on said drive shaft, a driven clutch member carried by the related driven means to provide a direct drive connection through said driving and driven clutch members from said drive shaft to said driven means, and'reverse driving means between said drive shaft and said driven means, said direct drive connection through said forward driving and driven clutch members being wholly independent of elements of said reverse driving means; and means for controlling each of said clutch units independently and selectively to drive said driven meansfrom said drive shaft through either the forward or reverse driving means thereof.

26. In a tractor including a frame, traction means at opposite sides thereof, and a motor carried by said frame to drive said traction means; means for transmitting motion from said motor to said traction means to drive the same selectively and independently in either direction; said motion transmitting means including a 'pair of clutch units, a drive shaft common to said units, a driving connection from said motor to said drive shaft, driven means in driving connection with the respective traction means, each of said clutch units including a forward driving clutch member mounted on said driveshaft, a driven clutch member carried by the related driven means to provide adirect drive connection through said driving and driven clutch members from said drive shaft to said driven means, and reverse driving means between said drive shaft and said driven means, said direct drive connection through said forward driving and driven clutch members being wholly independent of elements of said reverse driving means; and means for controlling each of said clutch units independently and selectively to drive said driven means from said drive shaft through either the forward or reverse driving means thereof, said control means comprising two independently operable movable control members each having a forward-drive, a reverse-drive and a neutral-rest position, means common to both movable members for releasably locking them in the neutralrest position, and means to render said locking means inoperative when either of said members is in other than the neutral-rest position.

ALBERT W. BONHAM, JR. ALVIN B. BONHAM. 

